topic Re: Modeled NPT threads in Fusion Manufacture Forum

Modeled NPT threads

benjamintoews — Thu, 06 Apr 2023 16:41:56 GMT

Where did the modeled NPT threads go?

I thought i was missing some setting but i looked back in previous models that had tapered pipe threads and they are all changed to cosmetic or whatever its called.

I see there's a setting on the browser now, did that change something?

Re: Modeled NPT threads

seth.madore — Thu, 06 Apr 2023 17:06:54 GMT

Admittedly, I haven't had need for any NPT holes, but I'm fairly certain we've never had a "modeled" option for "Taper Thread" in the Hole Command.

Which setting are you referring to "on the browser"?

Re: Modeled NPT threads

benjamintoews — Thu, 06 Apr 2023 17:09:47 GMT

Ok. The light was starting to dawn. The option was probably never there.

I see there is a workaround but I don’t think I have to have this option. Hopefully someday it’s added.

Thanks!

Re: Modeled NPT threads

Warmingup1953 — Thu, 06 Apr 2023 19:45:32 GMT

Internal yes (Sort of):

here

External not

Re: Modeled NPT threads

fflesh — Tue, 12 Dec 2023 06:26:53 GMT

Seth, With all due respect it doesn't matter whAt you have required but what the community you service requires and calls for. ALLLLLLLL of North America uses NPT or American Pipe standard threads and to eliminate for the sake OF DIN PIPE THREADS is a definitive issue AutoDesk has a separation issue with the needs of the manufacturing community. I mean.....NPT threads for turning. Should I just spend $10K on a Rigid Branded Pipe Threading machine? I have some glass impregnated teflon I need to machine a custome sized NPT thread into/ on. This software is becoming preventative tbh. I spent the money but am met with unreasonable and unsolicited changes to the lathe programming. Sorry to be harsh but this is what I use to make money and feed myself with. BobCAD doesn't have these issues. I am harsh and unforgiving but someone is living comfy with their choices at AutoDesk while I struggle with what THEY sold me.

Re: Modeled NPT threads

seth.madore — Thu, 14 Dec 2023 19:19:42 GMT

@fflesh

Hey there.

We didn't remove anything. It was never an option to create NPT threads natively. We're not having a bias towards one unit system or another, it's just been a known limitation.

There are several ways to do what you're trying without actually modeling the threads in your part. Model a tapered hole/post and apply a threadmill or turning/thread toolpath to it.

Re: Modeled NPT threads

fflesh — Sat, 16 Dec 2023 11:13:47 GMT

I never implied NPT disappeared. The fact its not a basic option is absurd to me. I live in Canada and will NEVER encounter one single EURO standard. If I wanted to use work arounds I would just buy the Rigid Pipe Threading machine. In 1.5 yrs Id pay it off without the hassle of software work arounds. NPT.....My opinion is that in North America any EURO standard should have the work around and a basic American NPT thread should be easily attainable without a buncha jibba jabba. A basic DEFAULT. Luckily I can program that thread at the control panel on my Haas Lathe. Why should I have to scab together bits of programming from different software platforms tho to make a simple single diameter part with a tapered thread?
Im harsh because I gave my money more than once for this software and times like this shouldnt cost me money.

Re: Modeled NPT threads

seth.madore — Sat, 16 Dec 2023 12:28:48 GMT

@fflesh well, it's going to continue to be absurd to you. It's a modeling challenge that we've not invested time into fixing yet. It's not a preference for one standard over another, it's just simple "straight threads are easy, tapered are not". There are workarounds that aren't as absurd as buying a $10k pipe threader; a quick 1-2 minute model of a tapered boss is sufficient.

Re: Modeled NPT threads

bstewart6N4AT — Thu, 21 Nov 2024 23:27:56 GMT

Except for the grumpy back and forth here, there is a more basic question I have. If it is so "easy" for users to model a tapered thread using a workaround, then why is it so hard to add modeled NPT threads to the hole command? A lot of people use NPT threads, and I really don't want to dig through Machinery's Handbook every time. What I can do, and what I should need to spend extra time on are completely different things. F360 is being sed more and more in industry, and these type of enhancements need to be added as the usage grows.

Re: Modeled NPT threads

seanwalinga — Sun, 29 Dec 2024 22:34:19 GMT

Hi Seth,

It seems like users have figured out the thread angles and specs to make NPT threads in Fusion. It seems like you guys could just use those settings and make an add-on or plug-in or something. I am currently searching for those settings to build NPT threads - I used them before and they work well. I just lost my notes so I'm looking again. With the huge surge in 3D printing for advanced plastics and also metals, having the NPT threads modeled is going to be much more helpful.

Re: Modeled NPT threads

rainabba — Sun, 19 Jan 2025 18:35:37 GMT

As a software developer with decades of experience, I can assure others this is a conscious choice they've made since they first introduced modeled threads. They choose to implement them for nearly all standards save for those needed in North America. "a quick 1-2 minute model of a tapered boss is sufficient." It's not a technical issue despite "straight vs tapered". It's just another algorithm with new UI elements.

To claim there is any reasonable workaround is to acknowledge that it's not a technical limitation, but a business choice. Business decides what features and bugs get time and/or released. Business decided what standards would be implemented and they've decided NOT to put time into NPT because it wasn't "low-hanging fruit" the same way straight threads were. If a user can so easily workaround the lack of functionality, it should be trivial for the devs to implement that well-understood pattern. Business must bless the activity though and clearly they won't considering how many years customers have made this issue known.

Re: Modeled NPT threads

seanwalinga — Thu, 20 Feb 2025 22:07:56 GMT

For those that are looking.

I have the settings for 1/4 and 3/8 NPT. With a little trial and error, you could probably figure out other sizes as well. These settings have been printed on FDM and resin and they work well for internal threads (like a nut). Adjustments would be needed for outer threads (like a bolt).

These settings are using the COIL tool and metric.

1/4 = diam 13.72mm / revolutions 18 / pitch -1.41122mm / angle -1.78333 / section Triangle external / section position Inside / section size 3.43mm / operation Cut

3/8 = diam 17.15mm / revolutions 18 / pitch -1.41122mm / angle -1.78333 / section Triangle external / section position Inside / section size 4.00mm / operation Cut

If you google "NPT thread dimensions", you get multiple charts that'll give you the dimensions you need for internal and external threads.

revolutions = threads per inch

pitch = thread pitch

diam = pipe outside diameter

Good luck everyone.

"May your prints be strong and smooth."

Re: Modeled NPT threads

andy.i.httm — Thu, 27 Feb 2025 21:57:50 GMT

After all these years and still not having American pipe threads is really disappointing.

Re: Modeled NPT threads

j_r_alaimo — Thu, 08 May 2025 05:58:53 GMT

If anyone is still in need of NPT threads for fusion, I have a solution for you:

https://cults3d.com/en/3d-model/tool/fusion360-npt-thread-non-tapered-nps-library

This amazing person made them all and you can download them for free right now. You'll have to copy the extracted .xml file into a specific folder hidden in several nested fusion 360 folders (which are different depending on windows / osx). Follow the link below for instructions on finding the right folder for the .xml:

https://www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/Custom-Threads-in-Fusion-360.html

After copying the .xml into the correct folder, you should be able to reopen fusion and select NPT as an option under the Create > Threads tool. Make sure you select the "Modeled" option before exporting to .stl. Enjoy!

Re: Modeled NPT threads

jordan — Tue, 17 Jun 2025 01:48:05 GMT

Wow. Thanks for the details and the links - it's much appreciated.

This whole process of getting one of the most common thread standards added, by default, is "in the bottom of a locked filing cabinet stuck in a disused lavatory with a sign on the door saying 'Beware of the Leopard'” level of petty on the part of AutoDesk. OTOH, when they send out the next survey asking me why I won't spend $500 for hobby software, I'll know what to tell them now.

Re: Modeled NPT threads

brad_francola — Mon, 08 Sep 2025 20:09:35 GMT

@seth.madore does this NPT pipe thread thing continue to be a limitation today?

Re: Modeled NPT threads

CamLostine — Mon, 08 Sep 2025 20:53:54 GMT

Thanks for these! It's interesting they say they don't include NPS/NPT because it'd be more work for them, but for the NPS threads it's just an XML file they have to include! It also sucks that every time they update the program it wipes your custom thread files out. Seems like they are using a temp folder for the thread types on the thread function.

But the file you link only covers NPS (National Pipe Straight) and not NPT (National Pipe Taper). The threading function seems to only work as a straight thready but it would be awesome if they did a taper thread. You CAN add tapered threads through the "Hole" function but there is no option to make them modeled, which hinders machining.

Re: Modeled NPT threads

seth.madore — Mon, 08 Sep 2025 23:39:33 GMT

@brad_francola wrote:

@seth.madore does this NPT pipe thread thing continue to be a limitation today?

Yup 😞

Re: Modeled NPT threads

TheShaytoon — Sun, 04 Jan 2026 17:31:15 GMT

This is by no means an elegant solution, but you can download NPT models from McMaster Carr catalog and fuse them into your models...

Re: Modeled NPT threads

B.E.Cox — Tue, 17 Feb 2026 00:33:30 GMT

It is beyond embarrassing that Autodesk can't figure out how to model NPT threads and suggests that users turn to user-sourced hacky workarounds.

Seriously, guys, there's a reason Fusion is not the key player in the CAD segment. It's kind of embarrassing that you charge money for this product sometimes.

Autodesk staff, aren't you kind of ashamed at this?